Species · BCR 4 · BBS 2025 Release · 1966–2024

Black-billed Magpie In BCR 4

Black-billed Magpie in BCR 4 has surged: up 98% on the route-weighted index since 1978.

+98%Since 1978
35Routes In Region
45Years

Notable Signals

long arc increasecomputed index

Black-billed Magpie has surged in BCR 4: up 98% on the route-weighted index since 1978.

Forecast

If the recent trend holds, Black-billed Magpie in BCR 4 is projected to rise about 19% by 2029 — from 1.1 in 2024 to a central estimate of 1.4 (95% range 0.41–2.3). A 5-year backtest shows a typical error of ±12.4%, with 100% of held-out values landing inside the 95% band.

+19%Change by 2029
1.4Projected 2029 index
0.412.395% range
±12.4%Backtest error
19762029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected index95% low95% high
20251.30.402.3
20261.40.402.3
20271.40.402.3
20281.40.412.3
20291.40.412.3

Routes In BCR 4

Routes recording Black-billed Magpie in BCR 4.
CohoeALASKA142023
KachemakALASKA142024
Anchor RiverALASKA132024
HomerALASKA91982
SavageALASKA72024
KalifonskyALASKA62023
ToklatALASKA52021
SourdoughALASKA52022
SlanaALASKA32024
Goose BayALASKA31982
Hatcher PassALASKA32024
CottonwoodALASKA31990
Mccarthy Rd2ALASKA31999
MaclarenALASKA21986
WasillaALASKA21983
Seven LakesALASKA22023
Ft. RichrdsnALASKA22017
Birch LakeALASKA12019
ChistochinaALASKA12022
MonahanALASKA12019
CantwellALASKA12015
Skilak LakeALASKA11985
WillowALASKA12024
Kenny LakeALASKA12019
Swan Lake RdALASKA12022

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.